stdlib: add __slots__

stdlib/@tests/stubtest_allowlists/darwin-py310.txt

@@ -41,6 +41,7 @@ xml.etree.cElementTree.XMLPullParser.flush
 xml.parsers.expat.XMLParserType.GetReparseDeferralEnabled
 xml.parsers.expat.XMLParserType.SetReparseDeferralEnabled
 xml.sax.expatreader.ExpatParser.flush
+zipfile.ZipInfo.__slots__
 
 
 # =============================================================

stdlib/@tests/stubtest_allowlists/darwin-py39.txt

@@ -50,6 +50,7 @@ xml.etree.cElementTree.XMLPullParser.flush
 xml.parsers.expat.XMLParserType.GetReparseDeferralEnabled
 xml.parsers.expat.XMLParserType.SetReparseDeferralEnabled
 xml.sax.expatreader.ExpatParser.flush
+zipfile.ZipInfo.__slots__
 
 
 # =============================================================

stdlib/@tests/stubtest_allowlists/win32-py310.txt

@@ -42,7 +42,7 @@ xml.etree.cElementTree.XMLPullParser.flush
 xml.parsers.expat.XMLParserType.GetReparseDeferralEnabled
 xml.parsers.expat.XMLParserType.SetReparseDeferralEnabled
 xml.sax.expatreader.ExpatParser.flush
-
+zipfile.ZipInfo.__slots__
 
 # =============================================================
 # Allowlist entries that cannot or should not be fixed; <= 3.12

stdlib/@tests/stubtest_allowlists/win32-py39.txt

@@ -51,7 +51,7 @@ xml.etree.cElementTree.XMLPullParser.flush
 xml.parsers.expat.XMLParserType.GetReparseDeferralEnabled
 xml.parsers.expat.XMLParserType.SetReparseDeferralEnabled
 xml.sax.expatreader.ExpatParser.flush
-
+zipfile.ZipInfo.__slots__
 
 # =============================================================
 # Allowlist entries that cannot or should not be fixed; <= 3.12

stdlib/_collections_abc.pyi

@@ -103,5 +103,6 @@ class dict_items(ItemsView[_KT_co, _VT_co]):  # undocumented
 if sys.version_info >= (3, 12):
     @runtime_checkable
     class Buffer(Protocol):
+        __slots__ = ()
         @abstractmethod
         def __buffer__(self, flags: int, /) -> memoryview: ...

stdlib/_threading_local.pyi

@@ -7,6 +7,7 @@ __all__ = ["local"]
 _LocalDict: TypeAlias = dict[Any, Any]
 
 class _localimpl:
+    __slots__ = ("key", "dicts", "localargs", "locallock", "__weakref__")
     key: str
     dicts: dict[int, tuple[ReferenceType[Any], _LocalDict]]
     # Keep localargs in sync with the *args, **kwargs annotation on local.__new__
@@ -16,6 +17,7 @@ class _localimpl:
     def create_dict(self) -> _LocalDict: ...
 
 class local:
+    __slots__ = ("_local__impl", "__dict__")
     def __new__(cls, /, *args: Any, **kw: Any) -> Self: ...
     def __getattribute__(self, name: str) -> Any: ...
     def __setattr__(self, name: str, value: Any) -> None: ...

stdlib/asyncio/events.pyi

@@ -73,6 +73,7 @@ class _TaskFactory(Protocol):
     def __call__(self, loop: AbstractEventLoop, factory: _CoroutineLike[_T], /) -> Future[_T]: ...
 
 class Handle:
+    __slots__ = ("_callback", "_args", "_cancelled", "_loop", "_source_traceback", "_repr", "__weakref__", "_context")
     _cancelled: bool
     _args: Sequence[Any]
     def __init__(
@@ -85,6 +86,7 @@ class Handle:
         def get_context(self) -> Context: ...
 
 class TimerHandle(Handle):
+    __slots__ = ["_scheduled", "_when"]
     def __init__(
         self,
         when: float,

stdlib/asyncio/protocols.pyi

@@ -6,21 +6,26 @@ from typing import Any
 __all__ = ("BaseProtocol", "Protocol", "DatagramProtocol", "SubprocessProtocol", "BufferedProtocol")
 
 class BaseProtocol:
+    __slots__ = ()
     def connection_made(self, transport: transports.BaseTransport) -> None: ...
     def connection_lost(self, exc: Exception | None) -> None: ...
     def pause_writing(self) -> None: ...
     def resume_writing(self) -> None: ...
 
 class Protocol(BaseProtocol):
+    # Need annotation or mypy will complain about 'Cannot determine type of "__slots__" in base class'
+    __slots__: tuple[()] = ()
     def data_received(self, data: bytes) -> None: ...
     def eof_received(self) -> bool | None: ...
 
 class BufferedProtocol(BaseProtocol):
+    __slots__ = ()
     def get_buffer(self, sizehint: int) -> ReadableBuffer: ...
     def buffer_updated(self, nbytes: int) -> None: ...
     def eof_received(self) -> bool | None: ...
 
 class DatagramProtocol(BaseProtocol):
+    __slots__ = ()
     def connection_made(self, transport: transports.DatagramTransport) -> None: ...  # type: ignore[override]
     # addr can be a tuple[int, int] for some unusual protocols like socket.AF_NETLINK.
     # Use tuple[str | Any, int] to not cause typechecking issues on most usual cases.
@@ -30,6 +35,7 @@ class DatagramProtocol(BaseProtocol):
     def error_received(self, exc: Exception) -> None: ...
 
 class SubprocessProtocol(BaseProtocol):
+    __slots__: tuple[()] = ()
     def pipe_data_received(self, fd: int, data: bytes) -> None: ...
     def pipe_connection_lost(self, fd: int, exc: Exception | None) -> None: ...
     def process_exited(self) -> None: ...

stdlib/asyncio/transports.pyi

@@ -8,6 +8,7 @@ from typing import Any
 __all__ = ("BaseTransport", "ReadTransport", "WriteTransport", "Transport", "DatagramTransport", "SubprocessTransport")
 
 class BaseTransport:
+    __slots__ = ("_extra",)
     def __init__(self, extra: Mapping[str, Any] | None = None) -> None: ...
     def get_extra_info(self, name: str, default: Any = None) -> Any: ...
     def is_closing(self) -> bool: ...
@@ -16,11 +17,13 @@ class BaseTransport:
     def get_protocol(self) -> BaseProtocol: ...
 
 class ReadTransport(BaseTransport):
+    __slots__ = ()
     def is_reading(self) -> bool: ...
     def pause_reading(self) -> None: ...
     def resume_reading(self) -> None: ...
 
 class WriteTransport(BaseTransport):
+    __slots__ = ()
     def set_write_buffer_limits(self, high: int | None = None, low: int | None = None) -> None: ...
     def get_write_buffer_size(self) -> int: ...
     def get_write_buffer_limits(self) -> tuple[int, int]: ...
@@ -32,13 +35,16 @@ class WriteTransport(BaseTransport):
     def can_write_eof(self) -> bool: ...
     def abort(self) -> None: ...
 
-class Transport(ReadTransport, WriteTransport): ...
+class Transport(ReadTransport, WriteTransport):
+    __slots__ = ()
 
 class DatagramTransport(BaseTransport):
+    __slots__ = ()
     def sendto(self, data: bytes | bytearray | memoryview, addr: _Address | None = None) -> None: ...
     def abort(self) -> None: ...
 
 class SubprocessTransport(BaseTransport):
+    __slots__ = ()
     def get_pid(self) -> int: ...
     def get_returncode(self) -> int | None: ...
     def get_pipe_transport(self, fd: int) -> BaseTransport | None: ...
@@ -47,4 +53,5 @@ class SubprocessTransport(BaseTransport):
     def kill(self) -> None: ...
 
 class _FlowControlMixin(Transport):
+    __slots__ = ("_loop", "_protocol_paused", "_high_water", "_low_water")
     def __init__(self, extra: Mapping[str, Any] | None = None, loop: AbstractEventLoop | None = None) -> None: ...

stdlib/asyncio/trsock.pyi

@@ -14,6 +14,7 @@ _WriteBuffer: TypeAlias = bytearray | memoryview
 _CMSG: TypeAlias = tuple[int, int, bytes]
 
 class TransportSocket:
+    __slots__ = ("_sock",)
     def __init__(self, sock: socket.socket) -> None: ...
     @property
     def family(self) -> int: ...

stdlib/contextlib.pyi

@@ -47,6 +47,7 @@ _CM_EF = TypeVar("_CM_EF", bound=AbstractContextManager[Any, Any] | _ExitFunc)
 # allowlist for use as a Protocol.
 @runtime_checkable
 class AbstractContextManager(ABC, Protocol[_T_co, _ExitT_co]):  # type: ignore[misc]  # pyright: ignore[reportGeneralTypeIssues]
+    __slots__ = ()
     def __enter__(self) -> _T_co: ...
     @abstractmethod
     def __exit__(
@@ -58,6 +59,7 @@ class AbstractContextManager(ABC, Protocol[_T_co, _ExitT_co]):  # type: ignore[m
 # allowlist for use as a Protocol.
 @runtime_checkable
 class AbstractAsyncContextManager(ABC, Protocol[_T_co, _ExitT_co]):  # type: ignore[misc]  # pyright: ignore[reportGeneralTypeIssues]
+    __slots__ = ()
     async def __aenter__(self) -> _T_co: ...
     @abstractmethod
     async def __aexit__(

stdlib/ctypes/_endian.pyi

@@ -3,10 +3,14 @@ from ctypes import Structure, Union
 
 # At runtime, the native endianness is an alias for Structure,
 # while the other is a subclass with a metaclass added in.
-class BigEndianStructure(Structure): ...
+class BigEndianStructure(Structure):
+    __slots__ = ()
+
 class LittleEndianStructure(Structure): ...
 
 # Same thing for these: one is an alias of Union at runtime
 if sys.version_info >= (3, 11):
-    class BigEndianUnion(Union): ...
+    class BigEndianUnion(Union):
+        __slots__ = ()
+
     class LittleEndianUnion(Union): ...

stdlib/dataclasses.pyi

@@ -170,6 +170,37 @@ class _DefaultFactory(Protocol[_T_co]):
     def __call__(self) -> _T_co: ...
 
 class Field(Generic[_T]):
+    if sys.version_info >= (3, 14):
+        __slots__ = (
+            "name",
+            "type",
+            "default",
+            "default_factory",
+            "repr",
+            "hash",
+            "init",
+            "compare",
+            "metadata",
+            "kw_only",
+            "doc",
+            "_field_type",
+        )
+    elif sys.version_info >= (3, 10):
+        __slots__ = (
+            "name",
+            "type",
+            "default",
+            "default_factory",
+            "repr",
+            "hash",
+            "init",
+            "compare",
+            "metadata",
+            "kw_only",
+            "_field_type",
+        )
+    else:
+        __slots__ = ("name", "type", "default", "default_factory", "repr", "hash", "init", "compare", "metadata", "_field_type")
     name: str
     type: Type[_T] | str | Any
     default: _T | Literal[_MISSING_TYPE.MISSING]
@@ -355,6 +386,7 @@ def is_dataclass(obj: object) -> TypeIs[DataclassInstance | type[DataclassInstan
 class FrozenInstanceError(AttributeError): ...
 
 class InitVar(Generic[_T]):
+    __slots__ = ("type",)
     type: Type[_T]
     def __init__(self, type: Type[_T]) -> None: ...
     @overload

stdlib/fractions.pyi

@@ -14,6 +14,7 @@ class _ConvertibleToIntegerRatio(Protocol):
     def as_integer_ratio(self) -> tuple[int | Rational, int | Rational]: ...
 
 class Fraction(Rational):
+    __slots__ = ("_numerator", "_denominator")
     @overload
     def __new__(cls, numerator: int | Rational = 0, denominator: int | Rational | None = None) -> Self: ...
     @overload

stdlib/hmac.pyi

@@ -20,6 +20,7 @@ def new(key: bytes | bytearray, msg: ReadableBuffer | None, digestmod: _DigestMo
 def new(key: bytes | bytearray, *, digestmod: _DigestMod) -> HMAC: ...
 
 class HMAC:
+    __slots__ = ("_hmac", "_inner", "_outer", "block_size", "digest_size")
     digest_size: int
     block_size: int
     @property

stdlib/importlib/metadata/__init__.pyi

@@ -97,6 +97,7 @@ class EntryPoint(_EntryPointBase):
 
 if sys.version_info >= (3, 12):
     class EntryPoints(tuple[EntryPoint, ...]):
+        __slots__ = ()
         def __getitem__(self, name: str) -> EntryPoint: ...  # type: ignore[override]
         def select(
             self,

stdlib/inspect.pyi

@@ -336,6 +336,7 @@ class _void: ...
 class _empty: ...
 
 class Signature:
+    __slots__ = ("_return_annotation", "_parameters")
     def __init__(
         self, parameters: Sequence[Parameter] | None = None, *, return_annotation: Any = ..., __validate_parameters__: bool = True
     ) -> None: ...
@@ -416,6 +417,7 @@ if sys.version_info >= (3, 12):
     def getasyncgenlocals(agen: AsyncGeneratorType[Any, Any]) -> dict[str, Any]: ...
 
 class Parameter:
+    __slots__ = ("_name", "_kind", "_default", "_annotation")
     def __init__(self, name: str, kind: _ParameterKind, *, default: Any = ..., annotation: Any = ...) -> None: ...
     empty = _empty
 
@@ -447,6 +449,7 @@ class Parameter:
     def __hash__(self) -> int: ...
 
 class BoundArguments:
+    __slots__ = ("arguments", "_signature", "__weakref__")
     arguments: OrderedDict[str, Any]
     @property
     def args(self) -> tuple[Any, ...]: ...

stdlib/ipaddress.pyi

@@ -22,6 +22,7 @@ def ip_interface(
 ) -> IPv4Interface | IPv6Interface: ...
 
 class _IPAddressBase:
+    __slots__ = ()
     @property
     def compressed(self) -> str: ...
     @property
@@ -33,6 +34,7 @@ class _IPAddressBase:
         def version(self) -> int: ...
 
 class _BaseAddress(_IPAddressBase):
+    __slots__ = ()
     def __add__(self, other: int) -> Self: ...
     def __hash__(self) -> int: ...
     def __int__(self) -> int: ...
@@ -105,6 +107,7 @@ class _BaseNetwork(_IPAddressBase, Generic[_A]):
     def hostmask(self) -> _A: ...
 
 class _BaseV4:
+    __slots__ = ()
     if sys.version_info >= (3, 14):
         version: Final = 4
         max_prefixlen: Final = 32
@@ -115,6 +118,7 @@ class _BaseV4:
         def max_prefixlen(self) -> Literal[32]: ...
 
 class IPv4Address(_BaseV4, _BaseAddress):
+    __slots__ = ("_ip", "__weakref__")
     def __init__(self, address: object) -> None: ...
     @property
     def is_global(self) -> bool: ...
@@ -156,6 +160,7 @@ class IPv4Interface(IPv4Address):
     def with_prefixlen(self) -> str: ...
 
 class _BaseV6:
+    __slots__ = ()
     if sys.version_info >= (3, 14):
         version: Final = 6
         max_prefixlen: Final = 128
@@ -166,6 +171,7 @@ class _BaseV6:
         def max_prefixlen(self) -> Literal[128]: ...
 
 class IPv6Address(_BaseV6, _BaseAddress):
+    __slots__ = ("_ip", "_scope_id", "__weakref__")
     def __init__(self, address: object) -> None: ...
     @property
     def is_global(self) -> bool: ...

stdlib/multiprocessing/managers.pyi

@@ -38,6 +38,7 @@ class Namespace:
 _Namespace: TypeAlias = Namespace
 
 class Token:
+    __slots__ = ("typeid", "address", "id")
     typeid: str | bytes | None
     address: _Address | None
     id: str | bytes | int | None

stdlib/numbers.pyi

@@ -61,12 +61,14 @@ class _IntegralLike(_RealLike, Protocol):
 #################
 
 class Number(metaclass=ABCMeta):
+    __slots__ = ()
     @abstractmethod
     def __hash__(self) -> int: ...
 
 # See comment at the top of the file
 # for why some of these return types are purposefully vague
 class Complex(Number, _ComplexLike):
+    __slots__ = ()
     @abstractmethod
     def __complex__(self) -> complex: ...
     def __bool__(self) -> bool: ...
@@ -109,6 +111,7 @@ class Complex(Number, _ComplexLike):
 # See comment at the top of the file
 # for why some of these return types are purposefully vague
 class Real(Complex, _RealLike):
+    __slots__ = ()
     @abstractmethod
     def __float__(self) -> float: ...
     @abstractmethod
@@ -153,6 +156,7 @@ class Real(Complex, _RealLike):
 # See comment at the top of the file
 # for why some of these return types are purposefully vague
 class Rational(Real):
+    __slots__ = ()
     @property
     @abstractmethod
     def numerator(self) -> _IntegralLike: ...
@@ -164,6 +168,7 @@ class Rational(Real):
 # See comment at the top of the file
 # for why some of these return types are purposefully vague
 class Integral(Rational, _IntegralLike):
+    __slots__ = ()
     @abstractmethod
     def __int__(self) -> int: ...
     def __index__(self) -> int: ...

stdlib/os/__init__.pyi

@@ -862,6 +862,7 @@ In the future, this property will contain the last metadata change time."""
 # on the allowlist for use as a Protocol starting in 3.14.
 @runtime_checkable
 class PathLike(ABC, Protocol[AnyStr_co]):  # type: ignore[misc]  # pyright: ignore[reportGeneralTypeIssues]
+    __slots__ = ()
     @abstractmethod
     def __fspath__(self) -> AnyStr_co: ...